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Cultivo consorciado de milho de segunda safra com espécies de adubo verde visando à diminuição da adubação nitrogenada de cobertura
(Universidade Federal de São Carlos, 2018-07-05) Gonçalves, Rodrigo Singulane; Soares, Marcio Roberto; https://lattes.cnpq.br/6337462438517339; https://lattes.cnpq.br/6740769477082553
Winter corn (second crop corn) has become the main autumn-winter crop in Brazil. In the 2016/2017 crop, the average productivity was 5,303 kg ha-1, surpassing that of the summer corn (first crop corn). With the expectations of increased productivity and expansion of the cultivated area, there will be a need to supplement sowing fertilization with N in topdressing fertilization, a practice often suppressed due to water deficit in the period of extemporaneous cultivation of winter corn. The use of green manure species between the crop row in consortium with winter corn has been recommended to maintain soil moisture. In addition, considering that the N of green manure can become available to the main crop through in vivo mechanisms in intercropping, it is possible to decrease the amount of N offered in topdressing fertilization. The aims of this study were: (i) to evaluate biometric, nutritional, and production parameters of the winter corn (hybrid 30A37 PW), cultivated in consortium with green manure species and with doses of nitrogen in topdressing; (ii) the degree of nitrogen fertilization suppression using green manure. The experiment was installed in a dystrophic Oxisol, with a randomized block design and a 4x3 factorial scheme, with five replicates. The treatments consisted of four conditions for establishing green manure (without green manure; Crotalaria spectabilis; Cajanus cajan; Crotalaria spectabilis + Cajanus cajan;) and three levels of nitrogen topdressing fertilization (0, 15, and 30 kg ha-1 of N ), 30 days after the emergency. Dry mass, stem diameter, plant height, number of leaves above the ear, weight of 1000 grains, number of rows per ear, number of grains per row, grain mass per ear, the mass of the ear without straw, the length and diameter of the ear, the height of insertion of the first ear, productivity, and leaf contents of N, P, K, Ca, Mg and S were evaluated. The treatments did not produce significant differences in biometric and productivity parameters, which were lower than those found in the scientific literature. Regardless of the treatment, leaf N levels were above the range considered adequate for winter corn. Except for the treatment in which Crotalaria spectabilis was grown between the crop row and the addition of 30 kg ha-1 of N in topdressing fertilization, all experimental conditions resulted in insufficient P foliar levels. Experimental plots with no intercropping with green manure resulted in plants with adequate K leaf levels. No insufficient leaf levels of Ca, Mg and S were observed. It was not possible to estimate the degree of nitrogen fertilization suppression for winter corn intercropped with green manure species. The average productivity, which varied from 2.2 to 2.4 t ha-1, was considered very low when compared to the average Brazilian productivity and was attributed to the inadequacy of the 30A37 PW hybrid to climatic zoning, to the deficiencies of P and K and probable Zn insufficiency.
Importância do núcleo parabraquial lateral no controle do equilíbrio hidromineral em modelo animal de hipertensão essencial
(Universidade Federal de São Carlos, 2018-07-05) Guillen, Camilla Dias; Andrade, Carina Aparecida Fabrício de; https://lattes.cnpq.br/9055280555067656; https://lattes.cnpq.br/9884709558405813
Excessive salt intake has been associated with the development or worsening of chronic diseases such as hypertension. Spontaneously hypertensive rats (SHR) have a typical increased sodium preference. The lateral parabrachial nucleus (LPBN) acts as an important inhibitory mechanism for sodium intake control, besides its involvement in cardiovascular control in normotensive rats. However, the involvement of LPBN in cardiovascular control and sodium appetite is still unknown in SHR. The aim for the present study was to evaluate cardiovascular responses and 0.3 M NaCl intake after α2-adrenergic receptors activation in LPBN in this model of essential hypertension. In SHR, bilateral injections of moxonidine (α2-adrenergic/imidazolinereceptors agonist) in LPBN increased 0.3 M NaCl intake induced by water deprivation – partial rehydration protocol (WD-PR), without changes in water intake. However, LPBN moxonidine injections did not significantly change 0.3 M NaCl or water intake induced by WD-RP in normotensive Holtzman rats. In normohydrated SHR moxonidine injections into the LPBN did not change 0.3 M NaCl and water intake, mean arterial pressure (MAP), heart rate (HR) and baroreflex responses. The WD-PR protocol did not change baseline values of MAP and HR in SHR, neither after LPBN moxonidine injections. It was also observed that LPBN moxonidine injections in SHR resulted in a positive sodium balance, characterized by increased 0.3 M NaCl intake during the sodium appetite test followed by increased renal sodium excretion and urinary volume at the end of the experiment. Therefore, present results show thatα2-adrenergic/imidazolinereceptors activation in the LPBN increases WD-PR-induced sodium appetite in SHR. This effectis not related to changes in arterial pressure. Therefore, we can conclude that LPBN inhibitory mechanisms contribute to limit sodium intake also in Spontaneously Hypertensive Rats.
Índice de Integridade Biótica para o município de Sorocaba (SP) utilizando comunidades de peixes
(Universidade Federal de São Carlos, 2018-07-05) Silva, Guilherme; Cetra, Maurício; https://lattes.cnpq.br/6775493342513120; https://lattes.cnpq.br/5205087039793385
The Biotic Integrity Index has been an effective biomonitoring tool utilizing freshwater fish assemblages. In tropical and subtropical countries, however, its use over time has been developing, although adaptation in these regions has begun more recently. This study aimed at the creation of a Biotic Integrity Index for the municipality of Sorocaba - SP, where it aims to assist in the monitoring of aquatic environments in the urban zone using as bioindicators the fish of streams. A total of 2492 individuals were collected in a total of 27 stretches, 23 in the urban area of the city of Sorocaba and 4 in the Ipanema National Forest in Iperó. An environmental protocol was also applied in all the excerpts to verify the physical characteristics of the streams and later used to promote correlations between the biotic variables. Seven variables were selected to compose the Biotic Integrity Index, being separated into three groups with a response capacity, such as species diversity, habitat and trophic function. Two streams were classified as excellent (7.5%), five as good (18.5%), five regular (18.5%), eight poor (29.5%), two very poor (7.5%), and five without fish (18.5%). The biotic integrity index proposed for this work presented a satisfactory correlation between the environmental conditions and the fish communities due to the presence of a environmental gradient capable of generalizing impacts in the urban region of the city of Sorocaba. This work has demonstrated that studies like this one besides being able to promote applicability and development of methods for environmental biological evaluations, also has as consequence a better knowledge of the freshwater fishes.
Síntese de 1,2,3-triazóis 1,4,5-trissubstituídos via catálise heterogênea empregando reações em micro-ondas e fluxo contínuo
(Universidade Federal de São Carlos, 2018-07-05) Dias, Cássio da Silva; Schwab, Ricardo Samuel; https://lattes.cnpq.br/6935890756504964; https://lattes.cnpq.br/4370694807878074
Heterocyclic compounds containing the 1,2,3-triazole nucleus have received special attention in the field of synthetic chemistry have seen that have a wide field of application in biological and material areas. In this work, a new methodology was developed through a more sustainable approach for the synthesis of 1,2,3-triazoles, employing microwave irradiation as a heating source for the 1,3-dipolar cycloaddition reaction. As dipolarophile, β-dicarbonyl compounds, commercially available and others prepared by means of transesterification reactions between methyl acetoacetate and different alcohols were used. As the dipole species, different organic azides were prepared via a diazonium salt formation reaction. The triazoles were synthesized using nanoparticles of copper oxide II as catalyst under microwave irradiation. This new protocol allowed the preparation of a broad scope of highly functionalized 1,4,5-trisubstituted 1,2,3-triazoles in the short reaction time, in good to excellent yields. At the end of the synthesis, a study was performed on the recovery of the nanocatalyst, being possible its use for up to 3 reactional cycles with good yields of triazoles. Still in the context of more sustainable methodologies, the continuous flow reactors have been successfully applied in the development of new synthetic methodologies, since the efficient transfer of heat and better mixing of the reactants, has implied a smaller amount of byproducts and high conversion rates, among other advantages. In this part of the work, a new methodology for the synthesis of 1,2,3-triazoles 1,4,5-trisubstituted was initiated, via a reaction of 1,3-dipolar cycloaddition between carbonyl substrates, and arylazides, with reactions catalyzed by molecular sieves under continuous flow regime catalysed by molecular sieves, obtaining high conversion rates in the triazoles.